A single media gateway (MG) chassis may be divided into many smaller virtual media gateways. One type of virtual media gateway has permanent resources, such as TDM (time division multiplex) channels or ATM (asynchronous transfer mode) PVCs (permanent virtual circuit), associated with them. These permanent resources are statically provisioned on the media gateway and are registered with the media gateway controller as semi-permanent terminations in ITU-T H.248 protocol. When these statically provisioned resources need to be used, the media gateway controller instructs the media gateway to manipulate the characteristics of these terminations. However, shared resources, such as IP ports and ATM SVCs (switched virtual circuit) as well as DSPs (digital signal processors), are not provisioned in these virtual media gateways. These resources are dynamically allocated to a task (a voice call normally) when they are needed and then released back to the resource pool after the task is completed. Another type of virtual media gateway does not have any permanent resources statically provisioned because it uses only shared resources. These virtual media gateways without provisioned permanent resources are simply logical entities terminating call control messages and then dynamically allocating and deallocating resources needed for specific tasks (or calls).
Under normal conditions, connections between media gateways are achieved via packet—either IP (Internet Protocol) or ATM—networks, which connect them together. For a call originated and terminated on the same media gateway (intra-MG calls), the bearer traffic is usually routed internally inside the media gateway using its own switching capabilities, either TDM switching or packet switching. However, for a call originated and terminated on two separated media gateways (inter-MG calls), the bearer traffic needs to be routed through external packet networks. The originating media gateway terminates the voice channel where the call is originated. If the originating voice channel is a TDM channel, the originating media gateway will convert the continuous TDM voice stream to discrete packets. The packets are sent from the originating media gateway to the terminating media gateway via a packet (IP or ATM) network. The terminating media gateway then sends the packets to the terminating voice channel. If the terminating voice channel is TDM, the terminating media gateway will convert the discrete packets back to continuous TDM stream. The packet network connecting the media gateways together plays an important role in completing the call.
Where a physical media gateway is divided into multiple virtual media gateways, a call originally viewed as an intra-MG call can be considered as an inter-MG call if the call involves two virtual media gateways. Typically, such calls would be treated as inter-MG calls and would need to go out to external packet networks for connections. Therefore, additional external resources would be needed to complete the task. These additional connections may also cause additional delays. To eliminate the need for additional external resources and the added delay, there is a need in the art for a method and system for connecting calls between virtual media gateways through the use of a special shortcut.